Throat plate raising attachments for sewing machines



A ril 29, 1969 1.. J. COULOMBE I THROAT PLATE RAISING ATTACHMENTS FORSEWING MACHINES Filed April 25, 1967 Sheet INVENTOR. Llonel J. CoulombeRNEY WITNESS:

April 29, 1969 1.. J. COULOMBE THROAT PLATE RAISING ATTACHMENTS FORSEWING MACHINES Filed April 25, 1967 Sheet INVENTOR. Llonel J. CoulombeATS ORNEY WITNESS: oleicb' m w g United States Patent US. Cl. 112-260 3Claims ABSTRACT OF THE DISCLOSURE A throat plate raising attachment fora sewing machine comprising a shim that is slideably disposed in theslideway of the bed slide, the closing of which will force the shimunder the throat plate to raise the same above the feed mechanism toenable the machine to be used for such sewing operations as darning orembroidering.

Background of the invention Summary of the invention In accordance withthe present invention a novel throat plate raising attachment isprovided for a sewing machine to render the feed mechanism thereofineffective. The attachment comprises a shim shiftably disposed acrossthe slide way with at least one throat plate engaging projectionextending outwardly therefrom. Closing of the opened bed slide willforce the throat plate engaging projection under the throat plate topermit the shim to raise the throat plate above the feed mechanism.

An object of the present invention is to provide an improved throatplate raising device which overcomes the prior art disadvantages; whichis simple, reliable, and economical; which is operated by the closing ofthe bed slide; which is an individual attachment; which is positivelysupported on and shiftable along a slideway to raise the throat platewithout interfering with the operation of the loop forming means; whichwill raise the yieldably held throat plate sufficiently to render thefeed mechanism inefiective; which will permit substantial uniformraising of the throat plate; which will enable the maintenance of acontinuous substantially at working surface; which permits easy operatorhandling of said device.

Other objects and advantages will be apparent from the followingdescription of one embodiment of the invention and the novel featureswill be particularly pointed out hereinafter in the claims.

Brief description of the drawings This invention is illustrated in theaccompanying drawings in which:

FIGURE 1 is a plan view of the novel throat plate raising devicedisposed on the slideway of an open bed slide,

FIGURE 2 is a plan view of the novel throat plate raising device, shownmostly in dotted lines, after it has been slid under the throat plate toraise the same on the closing of the bed slide,

3,440,987 Patented Apr. 29, 1969 FIGURE 3 is a sectional view takenalong line 33 of FIGURE 2,

FIGURE 4 is an enlarged view, part in section, taken along line 44 ofFIGURE 1,

FIGURE 5 is an enlarged view, part in section, taken along line 5-5 ofFIGURE 2,

FIGURE 6 is an enlarged perspective view of the novel throat plateraising device.

Description of the invention In the illustrated embodiment of theinvention the sewing machine shown may be of any conventional type usinga yieldably held throat plate abutted by a bed slide.

In FIGURES l-S the novel throat plate raising attachment designatedgenerally as 10 is associated with a sewing machine having a bed 11formed in a frame 12 in which is disposed a four motion feedingmechanism including a feedbar 14 to which is connected a feed dog 16.The usual lift and drive mechanism is associated with the bar 14, only apart of which is shown by the drive bar 18. A flat working surface 20 isformed at the top of bed 11 with the feed dog 16 being the only part ofthe feed mechanism that intermittently rises above the normal level ofsurface 20, the highest point of rising being shown in FIGURES 3, 4 and5.

The bed 11 is provided with an opening 22 that is partially bounded bythe feeding mechanism and has a centrally disposed loop forming means 24of the stitch forming instrumentalities otherwise not shown. Asubstantially U shaped recess ledge or slideway 26 is formed aboutopening 22 with the base thereof adjacent the dog 16. A throat plate 28covers the base end of the opening 22 and is partially supported byslideway 26 but principally supported by two bosses 30 and 32. Throatplate 28 is provided with a needle aperture 34 and apertures 36, 38 and40 through which the feed dog 16 intermittently extends.

A large headed positioning pin 42, illustrated best in FIGURE 3, isplaced in hole 44 of boss 32. A larger pin 46 is resiliently connectedto the underside of boss 30 after passing through hole 48 therein. Asnap ring 50 is connected to the lower end of the shank of pin 46 andserves to hold a coil spring 52 in slight compression about the shank soas to urge pin 46 downwardly at all times. Pin 46 has a large head 54immediately below which is a shank portion 56 of reduced diameter.Throat plate 28 has a substantially straight leading edge 58 and a slot60 extending inwardly from one side thereof of a width slightly largerthan the diameter of shank portion 56 but substantially smaller thanhead 54. Across from slot 60 throat plate 28 has a hole 52 of slightlylarger diameter than the head of pin 42.

Throat plate 28 is yieldably connected to bed 11 by placing the slot 60under head 54 so that shank portion 56 may pass therein on shifting ofthroat plate 28 across the slideway. Since pin 46 is yieldably held byspring 52 the mounting of throat plate 28 is readily accomplished. Onceslot 60 has shank portion 66 therein hole 63 is disposed over the headof pin 42.

Leading edge 58 is beveled as at 64 on either side immediately above andoverlaping slideway 26 for purposes more fully explained hereinafter. Abed slide 66 having a straight forward face 68 is slideably disposed onslideway 26 to open or close the portion of opening 22 not covered bythroat plate 28. A suitable winged spring member 70 is connected to bedslide 66 to permit sliding movement thereof while preventing accidentalremoval of bed slide 66 from slideway 26.

Normally, the upper surface of the throat plate 28 and bed slide 66 issubstantially at the same level as working surface 20 thus permittingfeed dog 16 to function in the conventional manner. However, whenever itis desired to render the feed dog 16 ineffective the novel throat plateraising attachment may be used.

FIGURE 6 shows the novel throat plate raising attachment 10 which may bedefined generally as a shim and including a base or transverse member 72having projections or legs 74 and 76 extending outwardly from either endthereof. The legs 74 and 76 may extend on one side of transverse member72 to define a substantially U shaped shim 10; or extend on both sidesof transverse member 72 so as to define the substantially H shaped shim10 shown in the drawings. Adjacent the legs 74 a web 78 is formed ontransverse member 72 to permit a hole 80 to be formed therein, whichhole 80 provides clearance for the passage of thread from loop formingmeans 24 during the sewing operation. Leg 76 has bifurcated leadingedges 82, 82 formed thereon to define a slot 84 of similar dimensions asslot 60. To prevent shim 10 from being incorrectly positioned the wordUP may be stamped inwardly of the bifurcated edges 82 as shown only inFIGURE 6. Each of the leg edges has a taper 86 with a thickness thatdecreases in a downwardly and outwardly direction away from transversemember 72. Shim 10 lies in a single plane except for a substantiallyperpendicular flat upturned portion or flange 88 formed at the rear oftransverse member 72 that terminates in a flat upper edge 90. Flange 88may serve as gripping means, and extends substantially the length oftransverse member 72 terminating a short distance before legs 74 and 86.Leading edge 82, forward face 68 and flange 88 will be parallel to eachother when placed on slideway 26. Also the total height of flange 88 isapproximately twice the thickness of shim 10.

Whenever the operator desires to perform such sewing functions asdarning or embroidering shim 10 will be placed under throat plate 28 soas to raise throat plate 28 an amount equal to the thlCkneSs of shim 10or approximately .045 inch, which is higher than the maximum rise offeed dog 16. This may be accomplished by opening bed slide 66 as shownin FIGURES 1 and 4. The width of shim 10 is substantially equal to thewidth of bed slide 66. After opening bed slide 66, shim 10 is placed onslideway 26 in the UP position with the and force the same to rise asshown in FIGURES 2, 3 and 5. The throat plate 28 rises simultaneously atthree 66 so as to form a continuous fiat surface. The cooperating bevel64 and taper 86 facilitate insertion of shim 10 under throat plate 28.

It will be understood that various changes in the details, materials,arrangements of parts and operating conditions which have been hereindescribed and illustrated in order to explain the nature of theinvention may be made by those skilled in the art within the principlesand scope of the invention as expressed in the claims.

Having thus set forth the nature of the invention, what I claim hereinis:

1. An attachment throat plate and bed slide raising device for use witha sewing macine having a bed in which a throat plate and a bed slidespan a bed opening and are mounted across oppositely facing recessedledges at each side of said opening to cover a portion of a feedmechanism and loop forming means and to form part of a flat worksupporting surface along which work is fed in a prescribed line, theattachment is adapted to e placed across said ledge upon opening of thebed slide and comprises:

(a) an elongated base member having a length adapted to span said bedopening and to extend between the ledges upon retraction of the bedslide,

(b) a pair of legs integrally formed on opposite ends of the base memberand adapted to be separately carried by the opposite ledges parallel tothe line of feed,

(c) each of the legs having a front portion and a back portion extendingoutwardly in opposite directions away from the base member,

(d) one edge of the base member having an upturned portion in a planeperpendicular to said legs and extending above the top surface of saidbase member a predetermined amount which does not exceed the thicknessof the throat plate or bed slide,

(e) means for enhancing the insertion of the legs 'beneath the throatplate and bed slide,

(f) the upturned edge adapted to 'be abutted by the bed slide upon theclosing thereof whereby the throat plate and the bed slide each can beraised an equal amount along a line parallel to the line of feed tomaintain a substantially smooth Work supporting surface.

2. The combination claimed in claim 1 wherein:

(a) the means for enhancing is a taper at the outermost extremities ofthe legs.

3. The combination claimed in claim 1 (a) a web extends between one ofsaid base member and an opening formed wherein: legs and said in saidweb.

References Cited UNITED STATES PATENTS 2,808,797 10/1957 Ayres 1122602,911,929 11/1959 Caldwell FOREIGN PATENTS 241,569 12/1911 Germany.

